Steam piston-valve



(No Model.)

' W. S. PHELPS.

STEAM PISTON VALVE.

Patented Aug. 8,, 1882.

' IlWENTOR & \QATTORNEYS.

WITNESSES:

UNITED STATES PATENT OFFICE.

WALTER S. PHELPS, OF WORTENDYKE, NEW JERSEY.

STEAM PISTON-VALVE.

SPECIFICATION forming part of Letters Patent No. 262,471, dated August8, 1882.

Application filed March 23, 1882.

To all whom it may concern Be it known that I, WALTER S. PHELPS, of\Vortendyke, in the county of Bergen and State of New Jersey, haveinvented a new and useful Improvement in Steam Piston-Valves, of whichthe following is a full, clear, and exact description.

My invention consists in a piston-valve of novel construction, combinedwith a cylinder and inclosing case or shell, as hereinafter describedand claimed, the object being to furnish a balanced valve reliable inaction and of durable construction.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar letters of reference indicatecorresponding parts in all the figures.

Figure l is a longitudinal section of a steamchest fitted with theimproved valve, and Fig. 2 is a transverse section on linear a. Fig. 3isa detail view.

A represents the side of an engine-cylinder, formed with steam -ports aa and exhaustport I).

B is the steam-chest.

G is the valve case or shell, secured upon cylinder A over the ports ab, and formed with slots 0 c and d in the under side, registering withthe ports of the cylinder. The shell 0 is formed with a circularaperture extending from end to end, and internally the shell is formedwith annular transverse grooves e e f, that connect with the slots 0 cand d.

D is a hollow cylinder, of a size to fit snugly in the longitudinalaperture of the shell, wherein the cylinder is firmly secured, and ofa'length to project at the ends of the shell. This cylinder D isprovided with apertures g, of suitable shape, opening into the groovescf of the shell, and placed as closely together as may be, sufficientspace being left between the opening for support of the piston-valve E,which works in the cylinder.

The piston or valve E is upon the end of a rod or stem, 25, and in itsgeneral construction consists of heads h h, separated by an annulargroove or exhaust-steamway, t. The heads h are packed to fit thecylinder steam-tight, so as to prevent leakage of steam into theexhaust-space z, and the reciprocation of the valve connects theopenings 9 c and ports a with the opening 9 d and port I), first at oneend and then at the other.

In detail the heads are made up of beveled (No model.)

collars k on the rod, formed with sleeves I, that receive splitcompressionrings at and packing-rings a, which are held between collars7c and washers 0, a nut at the outer end of rod t retaining the partssecurely. There are two com prcssion-rings m and packingrings a in eachhead, separated by a followerring, 1?, which is grooved radially 011 thesides toward the collar k. Between the inner ring m and sleeve 1 is aspace connecting with the grooves in ring p, so as admit steam behindthe eompression-rin g, and the space contains a coiled spring, q, forretaining the parts concentric. The outer ring at receives steam behindit directly through holes in washer 0 and in the sleeve l. The rings mserve to prevent leakage while the piston is passing the ports. Thefollower p cuts 011' the live steam from passing behind the innercompressionring m, so that while the outer ring is expanded by steamunder boiler-pressure the inner ring receives behind it the steam or hotgases at their pressure in the cylinder. The effect is to relieve thepressure in the cylinder to a certain extent before the exhaust opens,and thus relieve the valve of the excessive upward pressure at theexhaust end, which, in ordinary slide-valves, often lifts them fromtheir seat. The space may be enlarged to any extent required for reliefof the pressure. The two collars k k are separated by washers 4", thatgive the proper length to the valve and width to groove i. The shell 0is made with openings 8 in its upper side, extending into the groovesof, through which the position of the valve can be noted in setting it.These openings are covered by a plate, as shown, when the valve is inuse.

Having thus described my invention, I claim as new and desire to secureby Letters Patent- 1. The grooved follower-ring 1), combined with thecompressing-rings m and packingrings a of the piston-valve,substantially as and for the purpose set forth.

2. A piston-valve provided with two compression-rings, m, andpacking-rings a, separated by a follower, p, the outer ringsm beingfitted to receive steam from the chest and the inner rings from thecylinder, substantially as shown and described.

WALTER S. PHELPS.

Witnesses:

GEO. D. WALKER, G. SEDGWIGK.

